1. Field
The present invention pertains generally to a pedal for a bicycle or other foot-driven, crank-operated apparatus, and more particularly to such a pedal comprising coupling means in combination with conjugate means provided on the sole of a shoe for quickly and easily securing the shoe to the pedal for pedaling while also allowing rapid, safe disengagement of the shoe from the pedal during normal operation as well as in an emergency.
2. State of the Art
It has long been recognized that it is advantageous in bicycling and other similar pedaling applications to provide means for releasably engaging the shoe and foot of the operator to the pedal of the apparatus. Such attachment prevents the operator's foot from inadvertently slipping from the pedal as well as allowing the operator to exert a driving force on the pedal during both the downstroke as well as upstroke motion of the pedal and crank.
A variety of devices have been proposed in the prior art for providing releasable securement of the shoe of an operator to the pedal. The most rudimentary devices which have been used comprise a strap or toe cage attached to the pedal to extend over the toe and sometimes the instep of the shoe worn by an operator. Although such rudimentary devices can be used with generally any shoe worn by the operator, these devices have the disadvantages of being bulky, heavy and ackward to use. The latter disadvantage generally resulting because of the tendency for the weight of the strap or toe cage to rotate the pedal to an inoperating position in which the strap or toe cage faces downwardly. The operator must then reorientate the strap or toe cage to an operable position each time the operator engages the pedal.
Somewhat more sophisticated devices have been proposed for attaching a pedal gripping means to the bottom or sole of the shoe of the operator, with the gripping means being adapted for releasable connection to a corresponding or mating portion of the pedal. Examples of such connecting devices are disclosed in U.S. Pat. Nos. 458,608; 550,409; 595,388; 598,325; 3,788,163 and 4,488,453, in French Pat. Nos. 993,958; 967,277; 1,030,485; and 2,432,427, in British Pat. Nos. 16,829; 18,310 and 1,396,393 and in West German Pat. Nos. 3,000,015 and 3,149,345.
In all the devices of the above patents, the pedals have two major faces as is customary which can be used for the application of force. In most cases, however, only one face includes the mating portion for connection to the shoe of the operator. In these cases, as with the strap or toe cage as mentioned previously, the pedals are prone to rotate to a position in which the mating portion is not accessible, i.e. to a position in which it is facing downwardly from the operator. This problem has been alleviated in the past by utilizing balancing attachments of the type shown in U.S. Pat. No. 543,844. The balancing attachments unnecessarily increase the weight of the pedal and its complexity. In addition, the pedals of the prior art generally require an exaggerated motion of the shoe of the operator to engage and disengage the mating portions of the pedal and the operator's shoe. The mating portions generally must be aligned rather precisely, and the operator is apt to make several unsuccessful attempts to bring the mating portions into alignment before a successful move is made. The missed attempts are frustrating and can result in minor to more severe injury to the operator's foot as the shoe slips off or misses engagement with the pedal.
In U.S. Pat. No. 3,964,343, a pedal is disclosed which has a general prismatic configuration with at least three mutually congruent side faces. Each of the side faces are provided with mating means for mating with complementary means on the sole of the shoe of the operator. Theoretically, at least, the mating means can be secured substantially regardless of the position or attitude of any particular face of the pedal. In actual use, the mating means must be precisely aligned as with the other devices as discussed previously. The pedal generally rotates such that one of the side faces is oriented upwardly, but the mating means on the shoe of the operator must be aligned quite precisely with the complementary means on the side face of the pedal. Because of slight misalignments, the operator is likely to make several missed attempts which at best are frustrating and at worst can result in minor to more severe injury to the operator's foot as the shoe slips off or misses engagememt with the pedal.